Sustainability does not always come easy to the commercial world, demanding a change in culture that may go partly against the corporate grain, and the effort can sometimes benefit from the cooperation of a third party with the relevant expertise.

Mobile and broadband company O2 has taken this approach in its relationship with sustainable development charity Forum for the Future to provide expertise in its journey towards being a more sustainable company.

The charity supports O2's sustainability steering group, which is chaired by its chief executive Ronan Dunne chairs. All directors are expected to create a plan for their area of the business, which Dunne says is essential because when they are seen to be "stepping up to the plate, staff get a very clear message it is seen as a priority within the business."

Recent innovations within the steering group include all investment business cases now being scored and rated for their sustainability credentials.

Bill Eyres, who joined O2 as head of corporate responsibility and sustainability from the Body Shop, describes the relationship with Forum: "Starting in the second half of 2008 they carried out a review of our approach to sustainability. Then we had a half day session with the board in December 2008 to discuss findings and set out the strategy we had developed for the next three years.

"At its core, this is based around our strategic framework, which we dub the O2 Temple, with the roof being our belief in sustainability, the three 'customer pillars' being greener devices, services to help customers live more sustainable lives and supporting young people in the community. These are underpinned by O2 people and having our own house in order.

"Based around Forum's leadership model (beginner/performer/leader/pioneer) we set a goal of being a leader by the end of 2011 based around performance in the five key areas of the Temple. Crucially, success against this goal is judged by Forum not O2.

"At six monthly intervals they assess progress. So, for example, in July Jonathan Porritt did a teleconference with all the directors of the board to discuss our RAG (red/amber/green) status and advise on where we were progressing well and not so well.

"Every year we have a half day session with the board and Jonathan to discuss the findings of a more comprehensive review conducted around the business, as well as setting out the strategy for the next year. This includes an update on what other companies are doing as the boundaries of leadership are constantly been pushed by progressive businesses.

"In between these sessions, the sustainability team and other parts of the business work in partnership with Forum to drive our performance forward. For example, we worked together on eco-rating.

"The independence of Forum means they can act as a 'critical friend' and there is no room to hide where we are not performing. This addresses the tendency in any business to fudge areas of under-performance.

"This process is something we developed with Forum to ensure that we really drove our performance forward and didn't allow successes to create complacency. As Jonathan has said, achieving leadership is a steep climb."

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